Tom Renk built a garden made up mostly of hosta plants beneath a forest of black walnut trees in the backyard of his home in Sugar Grove, Ill.

CHICAGO— If you stand in the right spot in Tom and Karen Renk’s Sugar Grove, Ill., yard, you may notice that dozens of trees on the property are in perfect lines. That’s because the area used to be a black walnut nursery, and the 50- and 60-foot trees date back to the early 1950s. These trees are not gardener-friendly."We found out that black walnuts, from the leaves and the roots, give off this toxin, juglone, that keeps many other plants from growing," Tom Renk says.

So began the process of turning what had been an overgrown jungle into a beautiful yard. When they bought the lot 15 years ago, it was all scrub, he adds.

Working their way around the property, the Renks slowly cleared the undergrowth, killed weeds and after letting an area sit for a year or so, planted it. The soil was hostile — many plants would live a year or two at most, then die. But hostas thrived, juglone or not. There are now hundreds around the yard, all from stock he bought years ago.

There is also a lot of ground cover and some yews, all immune to the juglone. Day lilies and hydrangeas are also present, but have short life spans. Karen has several flowering plants in containers around the property for a little color. Also not bothered by the toxins: three artificial Christmas trees Renk placed along his back property line for privacy.

"I just dug holes and put them in," he says. "They’re in their tree stands and everything."

Soon, though, they’ll be obscured by yews that are thriving nearby. The overall feel of the yard — with a bridge, running water, pond, several paths and dappled sunlight — is of peace and tranquility.

"When you look around, you can see the challenges that we went through," Renk says. "We’ve probably spent thousands of dollars over the last 14 years trying to figure out what works. We roll with the punches. We figured out what we can’t do and went from there."

Renk is not alone in having to overcome adversity in the yard. Bad soil, bad topography and forgotten patches of land are all problems that can be surmounted.

Often neglected as homeowners focus elsewhere — the front yard for show, the back for entertainment — the side yard can be an asset. After all, it is often the way people move between the front and back yards. Also, many times it sits outside a large window and can be turned into an extension of a room.

"More often (side yards) are shady rather than sunny," says Phil Rosborough, president of Rosborough Partners (rosboroughpartners.com), a landscape design firm and contractor in Libertyville. "That’s fine, because they become lush green oases, in a sense. ... You can get this woodland-garden feel that’s quite endearing when looking out a formal dining room or family room."

Rosborough says an inviting side yard increases the level of interest elsewhere. "Sometimes (you can use) a pergola, an iron archway, some sort of element that draws you in, makes you want to head out that way and wander the property," he says.

A gently sloping lawn is one thing, an unmowable steep incline is something else.

"You can’t use that space if it’s your front or back yard," says Brian Casey, president of Outdoor Upgrades (outdoorupgradesinc.com), a landscaping firm based in Clarendon Hills. "One solution is to make the slope go away by bringing in a retaining wall to level off the grade, or bring in terraces to level the grade in segments."

Instead of a lawn, you can choose plants that are good on slopes, including native grasses such as switch grass or prairie dropseed; perennials, such as day lilies or hostas; and shrubs, such as juniper, sumac and chokeberry. Erosion-control blankets will help keep plants in place until roots get established.

"Like anything, they say form follows function," Casey says. "In reality, form follows your finances. The retaining wall is the most expensive, a blanket with seed below it is the least expensive, and a blanket with shrubs or perennials is somewhere in the middle."

It all starts with soil

Soil can make or break a garden. Heavy shade, rocky ground, clay or roots all present problems. A good first step might be to have it analyzed.

There are several kits available at retail garden stores that can be performed by the homeowner. Or, soil samples can be sent off to be tested.

"You can ... send it off to your cooperative extension, and they can tell you what’s in your soil," says Brian Casey. "(Or) somebody like me can come out and tell you that your soil stinks, or it’s OK, or we can amend it and then we’ll be OK."

He says that truly bad soil can be removed: take out 12 inches and replace it with 12 inches of healthy stuff. Sort-of bad soil can be beefed up with compost or gypsum. Chemicals are not as effective, he says. "Organic material adds drainage, volume, water-retaining capacity. You really make a lot more headway to changing the composition of that soil."

Garden guru Ken Druse has overcome heavy clay content on his property: "I added 3 inches of crushed gravel, 3 inches of compost, and turned it over to 12 inches. ... It has drainage, and the clay holds moisture. The gravel more than anything opened up the clay."